Tag Archives: Drug testing

Testing urine for cannabis does not improve on-the-job safety. It not only fails to measure impairment, a new study confirms cannabis users have an even lower accident risk than straight people.

The entire reasoning for drug testing workers and drivers is based on the assumption that any use will cause impairment and therefore users would endanger themselves and others around them. Now a new study has undermined the rationale for drug testing workers, by showing that the use of cannabis actually reduced the risk of accidents.

Investigators at the Luasanne University Hospital in Switzerland assessed the association between the use of cannabis and/or alcohol and the risk of injury among 486 patients aged 16 and older treated for various injuries. They found alcohol use in the six hours prior to injury was associated with a three-fold elevated relative risk compared with no alcohol use, but cannabis use was inversely related to risk of injury, with only 0.33 the risk compared to no use. Cannabis users had less injuries and were actually safer than alcohol drinkers or even straight people. Despite the study’s relatively small sample size, investigators concluded:

“The results for cannabis use were quite surprising. … The present study in fact indicated a ‘protective effect’ of cannabis use in a doseresponse relationship.”

A prior case-control study conducted by the University of Missouri also reported an inverse relationship between marijuana use and injury risk, finding, “Self-reported marijuana use in the previous seven days was associated … with a substantially decreased risk of injury.”

New Zealand and Australia follow a common standard for urine tests (AS/NZS 4308:2008), which is based on the US Standard. It permits only two methods for analysing urine: EMIT or GCMS. No other type of urine test, and no other type of test such as hair, saliva or sweat, meets the standard because they are unreliable and have a high rate of incorrect positives and negatives.

Only EMIT and GCMS urine tests can be used for evidential purposes, and any other type of test should be challenged.

EMIT tests are usually conducted at doctor’s surgeries or medical centres or places like MedLab.

GCMS tests are performed by the government-owned ESR, who have close ties with the police and who also analyse samples collected by NZ Drug Detection Agency Ltd, a privately-owned testing outfit run by former cops.

A simple on-site “screen” is sometimes used (that often resembles a home pregnancy kit) but these do not meet the standard and must be confirmed with proper lab analysis.

Urine tests are made to detect only the presence of THC-COOH, the non-psychoactive metabolite
of THC. A cut-off of 50ng/ml is allowed, supposedly to allow for any second hand smoke, but that figure is actually fairly arbitrary and based on little real science.

Evidence-based testing

Drug testing advocates claim it is about safety, but they only look for the inactive metabolite that remains after someone straightens up. THC from marijuana is converted to THC-COOH, which is fat soluble and can stay in the body for several months after use. Because urine analysis does not measure the presence of THC it cannot indicate when cannabis was inhaled or ingested, or whether a person is impaired.

If testing really was about on-the-job safety, as they claim, testers could just as easily look for the presence of THC itself, which is present while a person is high. Testers could set a limit for THC based on actual impairment.

In 2007 a research team led by Franjo Grotenhermen at from the Nova Institute in Germany showed a THC level in blood of 10ng/ml was equivalent to the legal drink-driving limit of 0.05. The study found that a level below this was not associated with an increased risk of injury.

Setting an THC level that is based on evidence and comparable to alcohol impairment would be more effective, just, and more widely accepted by workers and smokers.

Beating the test

The biggest question on the lips of most pot smokers is how long they have to stop in order to give a clean urine test. In anecdotal reports people say it takes anything from 2 days to 6 weeks to be clean, but there has not been a lot of actual research on the subject.

In a new study by the US National Institute on Drug Abuse in Maryland, USA, 60 regular cannabis users were monitored during 30 days of abstinence. Their urine was tested for the presence of THC-COOH, the non-psychoactive metabolite of THC. Surprisingly, researchers found there were considerable fluctuations between days with a positive urine test and days with a negative test during this period, rather than a constant decline in THC-COOH concentrations. The average number of days until the first negative test (THC-COOH below 50 ng/ml) was 3.2 days, while the average number of days until the last positive test was 15.4 days.

If you can’t wait that long, many stores now sell products designed to beat urine tests and maintain your privacy. But just as there are two officially sanctioned types of urine test, and others that are not approved, there are specialised products designed to work for each one. Make sure you get the right product for the test you are taking, or it may not work. One of the most widely used products is synthetic urine, that comes with a heating pad and pouring spout. It’s unisex, completely undetectable, and beats all types of urine test.

Synthetic cannabinoids designed to research the health effects and medical applications of cannabis are being sold as legal highs.

Brands such as Spice, Dream, Aroma, Space and possibly others have the cannabinoids, which have cannabislike effects but are usually not listed on the packets. Spice comes in several varieties and has been sold in New Zealand, Europe and Canada since 2002, while other brands have appeared more recently. The active ingredients are sprayed onto a base of herbs such as baybean, blue lotus, scullcap and lion’s tail. The products are often labelled as “incense” but are typically smoked. Anecdotal reports suggest they can also be used in a vaporiser.

Last year authorities in Germany asked a company called THC Pharm, which extracts natural cannabinoids and other psychoactive ingredients from plants, to find the active ingredient in
Spice. In December they announced they has isolated a “cannabimimetic” called JWH-018.

Then on 19 January 2009, the University of Freiburg in Germany announced that the other main active substance in Spice is related to a synthetic cannabinoid called CP 47,497. Different ratios of the two cannabinoids have apparently been used in the different varieties of Spice. US Customs was reported to have seized 100 pounds of Spice containing another potent synthetic cannabinoid called HU-210, but this has not been confirmed.

The synthetic cannabinoids activate cannabinoid receptors, causing similar effects to THC. More than one hundred synthetic cannabinoids already have been designed, many by researchers wanting to investigate the medicinal applications or health effects of cannabis, but who were stymied by anticannabis attitudes and overly restrictive government policies.

The irony is that these chemicals have crossed over onto the legal high market, also as a way of getting around cannabis prohibition. The synthetic cannabinoids in Spice do not resemble illegal cannabinoids, and therefore are not subject to laws restricting drug analogues. Analogues
must have similar molecular structures, and this is not the case.

Germany and Austria quickly banned Spice, but the products remain legal elsewhere. The problem for authorities is that because many more cannabinoids can be easily synthesized, the detected substances could easily be replaced by similar substances.

As well as being ineffective, drug testing school children is a draconian invasion of privacy, writes CHRIS FOWLIE

A recent conference held by the School Trustees Association has raised the ugly spectre
of drug testing extending even into primary schools.

Trustees and principals claimed that children as young as 5 had been caught taking drugs including cannabis to school, and some – including Otamatea High School principal Haydn Hutching – said testing the entire school population was the answer.

Some principals even said they would not seek the permission of – or even inform – parents before testing their children, claiming it was purely an educational or disciplinary matter.

Several schools are even sending drug-sniffing dogs on patrol in the classrooms. Palmerston North Boys’ High School conducts up to seven sniffer-dog searches a year, at a cost of $1500 each time. They receive no additional funding for this, so the money is taken from somewhere else – perhaps education resources or teacher’s wages.

The Ministry of Education doesn’t endorse drug searches in schools, spokesman Vince Cholewa told the Manawatu Evening Standard. He advises schools to seek legal advice if they do decide on searches. Mr Cholewa said only police have a right to search a school if drugs are suspected.

“Teachers aren’t above the law,” he said.

Student drug testing is not without its opponents, who insist research does not show drug testing policies make any difference to whether young people use drugs. A 2003 study sponsored by the US National Institute on Drug Abuse that included 94,000 students in 900 American schools, half with a drug testing policy and half without, found there was no difference in illegal drug use among students.

Drug tests violate students’ privacy, and could wrongly turn students into suspects if they refuse. As the programs expand, children may find their ability to object to the tests eroded. Tests could open the door to lawsuits. Most tests are imprecise and can show “false positives” as well as “false negatives”.

Only the GCMS test is truly accurate, but at a cost of at least $100 per test this is unlikely to be used by many schools, who will likely use the cheaper and less accurate screening cards (similar to a home pregnancy test).

Advocates of testing do not appear to have considered the consequences of violating the privacy of a child as young as 5 by forcing them to pee into a cup. At the very least, it could raise awareness of drugs in a child who until then had never thought about them.

What happens after a positive result is another concern. Many schools simply expel the student, which creates additional problems with alienation, delinquency and crime. Then again, these outcomes must by now be familiar to all prohibitionists.

The largest study of its kind has found drivers under the influence of cannabis are far less likely to be culpable in traffic accidents than drunk drivers, while several other recent studies have found no increased risk at all.

In an epidemiological study of approximately 8,000 accidents published in the British Medical Journal, researchers at the French National Institute for Research on Transportation and Safety found that alcohol intoxication and speeding were nearly ten times more likely to be an attributing factor in traffic fatalities than the use of cannabis.

Overall, researchers estimated that psychomotor impairment caused by cannabis was similar to that exhibited by drivers with blood alcohol concentrations (BAC) ranging from 0.02 to 0.05 per
cent. The legal limit in New Zealand for a driver over 20 is a BAC of 0.08

The relative risk for causing a fatal accident (where 1 = no increased risk) was 1.8-2.2 for cannabis. The risk factor was ten times that – about 20 – for alcohol above a BAC of 0.05, and also for speeding.

The study results have been provoking embarrassment among French government officials as they always claimed drugs are responsible for more deaths than speeding.

A recent study in Sweden found that the introduction of zero-concentration limits for THC and other drugs in the blood of drivers did not result in a reduction of driving under the influence of drugs (DUID). Researchers also noted that “the spectrum of drugs identified in blood samples from DUID suspects has not changed much since the zero-limit law was introduced” in 1999.

In another recent study, by researchers at the University of Maryland, the use of cannabis was not associated with the risk to cause a traffic accident. Researchers looked at the presence of
alcohol and illegal drugs in 6,581 drivers who were hospitalized at a shock trauma center from 1997 to 2001. Crash culpability was strongly associated with alcohol use. In contrast, this study did not find an association between crash culpability and cannabis use. Since only urine tests on cannabinoids were performed, it is not known whether drivers were actually under the influence of
cannabis – and since cannabis lingers long after use this makes the association even weaker.

In another recent study, researchers of the University of Victoria (Canada) investigated whether clients in treatment for problems related to the use of alcohol, cannabis, cocaine, or various combinations of these substances, had a higher risk to drive while impaired compared to a control group. 445 drivers under treatment were included. In the 8 years before treatment, every drug group except the “cannabis only” group had significantly more convictions for driving while impaired than controls.

UK Police use computer games to test impairment

Last year UK Police introduced traditional coordination tests to check for drivers impairment by drugs. Now the Home Office has turned to computer games. The traditional test included such tasks as instructing drivers to walk in a straight line, stand on one leg or touch their nose with their index finger. The Home Office believes the tests are too subjective, so has loaded a laptop with several “games” designed to assess the reactions of a motorist.

Drivers would be tested not only on their speed and dexterity but also the accuracy with which they performed the task. This is because while cannabis can slow reaction time, amphetamines quicken it – but also make individuals more prone to error.

Both these sorts of tests – traditional and computer – are more accurate than urine or saliva screens, as they measure actual impairment rather than past exposure to drugs.

A urine test may pick up cannabis residues that are several weeks old, while doing nothing to detect drivers impaired by fatigue or prescription drugs. Coordination- or computer-based tests are also less invasive, cheaper and quicker to operate.